A new dielectric material based on glass-ceramics for high-voltage (HV) capacitors has recently been developed. This material is sold under a trade name POWERAMIC™, by Schott AG of Mainz, Germany. The material is produced in a process of melting amorphous glass then subjecting the molten glass to a time-temperature profile which causes nano-sized crystal to grow in the glass. As a result, a highly homogenous and pore-free glass-ceramic is obtained.
This glass ceramic offers an extraordinarily high energy storage density and dielectric strength even at high temperatures which allows building very thin HV capacitors. By way of example a standard 2 nanofarad (nF) capacitor using a strontium titanate or barium titanate dielectric spacer, has a spacer-thickness of about 15 mm. Substituting the new glass-ceramic for the spacer would allow the dielectric thickness to be reduced to about 3 mm. Such a thin capacitor would be particularly advantageous in certain applications, for example, in the design of electric pulse generators for creating super-atmospheric discharges in excimer laser tubes.
A standard technique for assembling a two-terminal capacitor is to metallize surfaces of a thick dielectric spacer then solder bond metal electrodes to opposite sides of dielectric spacer. Soldering is not compatible with the above-discussed electric pulse generators. An alternative assembly technique preferably not requiring metallization would be more suitable.